Bonding machine



Dec. 15, 1953 SNYDER 2,662,967

BONDING MACHINE Filed July 3, 1948 2 Sheets-Sheet 1 3mm Ellsworth B. Snyder E. B. SNYDER BONDING MACHINE Dec. 15, 1953 2 Sheets-Sheet 2 Filed July 3, 1948 Wikneao:

?atentecl Dec. 15,1953

UNITED STATES PATENT OFFICE BONDING MACHINE Ellsworth B. Snyder, Somerville, N. .L, assignor to The Singer Manufacturing Company, Elizaboth, N. .1., a corporation of New Jersey Application July 3, 1948, Serial No. 36,907

This invention relates to electronic seaming machines which are more particularly adapted for bonding together plies of dielectric materials in continuous seams by the use of high frequency electric currents.

The present invention is in the nature of an improvement in the electronic seaming machine disclosed in the U. S. patent of H. Hacklander, No. 2,432,412, December 9, 1947, and has for its primary object to facilitate the bonding of materials varying in thickness during the seaming operation.

More specifically, this invention has for an object to provide means for automatically controlling the depth of work-penetration by a workengaging electrode of an electronic seaming machine throughout the seaming operation, and in accordance with variations in thickness of the plies being bonded.

Another object or" this invention is to provide work-controlled means for limiting the depth of penetration of the work by a work-engaging electrode.

A still further object of this invention is the provision of improved means for adjusting the minimum distance between the electrodes.

With the above and other objects in view, as will hereinafter appear, the invention comprises the devices, combinations and arrangements of parts hereinafter set forth and illustrated in the accompanying drawings of a preferred embodiment of the invention, from which the several features of the invention and the advantages attained thereby Will be readily understood by those skilled in the art.

In the drawings:

Fig. 1 is a vertical longitudinal section taken through the center of a machine embodying my invention.

Fig. 2 is a left end elevation, partly in section, of the machine shown in Fig. l, the face-plate of the machine being removed to expose the operating parts within the hollow head.

Figs. 3, 4 and 5 are detailed sectional views taken substantially along the lines 3-3, 44 and 5--5, respectively, of Fig. 2.

In the embodiment of this invention selected for illustration, my improved bonding machine has a frame comprising a bed carrying an overhanging bracket-arm l l terminating in a hollow head l2. .lournaled in bearings 13 and I l in the bracket-arm i l is a main shaft having a combined pulley and hand wheel I6 secured to its outboard end. The pulley 16 may be connected to any suitable source of power for the purpose of rotating the shaft l5. Journaled beneath the bed ID in the bearings I! and I8 is a second shaft [9 arranged parallel to the main shaft 15; and secured to the shaft l9 intermediate its bearings is a feed wheel 20, the periphery of which extends through a suitable slot in a plate 2 I carried by the bed 10.

The rotary shaft l5 imparts an intermittent step-by-step rotary movement to the shaft 19 through a mechanism comprising an eccentric 22 secured upon the main shaft IS, a block 23 surrounding the eccentric, and a connecting rod 24 having its forked upper end 25 engaging the sides of the block 23 and its lower end pivotally connected at 28 to an arm of a one-way clutch 28 which is secured to the shaft 19.

Adjacent its upper end, the connecting rod 24 has pivotally secured to it, at 29, one end of an anchor link 30, the other end of which is pivotally connected at 3| to a normally stationary crank arm 32 fulcruined on a shouldered screw 33 which is threaded into a bearing boss 34 formed on the bracket-arm I l. The arm 32 may be shifted about its pivot 33 by means of a bell-crank lever 35 pivotally secured at 36 to the bracket-arm II.

This mechanism for imparting a step-by-step motion to the feed wheel 20 is fully described in the patent to Hacklander, No. 2,432,412, dated Decemher 9, 1947, for a Bonding Machine, to which reference may be had for a more complete and de tailed description of the feeding mechanism.

Journaled in a bearing 40 carried by the hollow head l 2 is a vertically movable har 4| (Fig. 2) having secured to its lower end a bracket 42 which rotatably carries an upper feed wheel 43. The upper feed wheel 43 is inclined at an angle to the vertical and its periphery is adapted to overlie and cooperate with the lower feed wheel 29 to advance the material M. The vertically movable bar 4! is constantly urged downwardly by a flat spring 44, the ends of which bear upon the top of the bar 4! and stud 45. An adjusting screw 46 is located intermediate the ends of the spring for the purpose of varying the tension. This spring 44, through the bar 4|, functions to urge the top feed wheel 43 into yielding engagement with the lower feed wheel 20 to grip the material therebetween. From the above description, it will be understood that the feed wheels 20 and 43 impart a step-by-step motion to the material M.

The hollow head I2 is provided with vertically aligned bearings ll in which an endwise reciprocatory electrode carrying bar 48 is journaled. The bar 48 is urged downwardly by a coil compression spring 49 which encircles the bar 48 and reacts between the upper bearing 41 and a split collar 58 adjustably clamped to the bar 48. The split collar 58 carries a laterally extending pin having on its free end a roller 52 which is located in a guideway 53 (Fig. 1) formed in the hollow head of the machine. This construction prevents the bar 43 from turning in its bearings.

Threaded on the upper end 53 of the electrodebar 48 in an adjusting nut 55, with a reduced portion 56 which is embraced by a bracket 51', having a laterally extending pin 58 with a roller 59 journaled thereon and held against lateral displacement by a collar 6! In order to prevent the bracket 5? from turning and to guide it in a right line movement the bracket is formed with laterally extending spaced arms Bl (Fig. 5) which embrace a guide-rib 52 carried by the hollow head. It will be understood that the adjusting nut 55 turns relative to the bracket 51 and that the position of the bracket may be varied relative to the electrode-bar 48 by adjustment of the nut 55. The nut 55 is held in its adjusted position by means of a locking bolt as which bears on a shoulder 65 (Fig. 3) formed in the adjusting nut 55.

The roller 59 is located above and cooperates with an eccentric l? fixed on the free end of the main shaft l5 and, when the shaft [5 is rotated, the eccentric '5? will engage the roller 53 and raise the bar at against the action of the spring fit through a part of each revolution. of the shaft and will then move away from the roller and permit the spring 19 to force the bar 68 downwardly during the remaining portion of the revolution of the eccentric.

The bar as carries at its lower end an upper electrode 88 which cooperates with a lower electrode 8! located below the bed it of the machine. cross-section and is secured upon a block of insulating material 82 carried by a U-shaped strap 83 fixed to the under side of the bed it by the screws 85.

From the above it will be understood that the feed rollers 2t and 3 impart a forward feeding movement to the superposed plies of plastic material and then bring it to rest and that the upper electrode 8B is moved in timed relation with the feeding mechanism and engages the material while it at rest for the purpose of creating a bond between the plies. The electrodes 8% and 8! are supplied with a high frequency electrical current through a coaxial cable 35; the electrical connections between the source of high frequency current and the electrodes being fully shown and described in the above cited Hack-- lander patent to which reference may be had for a detail d description.

In order automatically to control the depth of work penetration of the electrode 86 'through out the seaming operation and in accordance with variations in thickness of the work presented to the electrodes, I have provided a variably positioned stop-mechanism which comprises an upstanding extension as on the end of the pressure-bar the upper end of which underlies a limb of a bell-crank lever 88 pivoted at.

89 to the upstanding ears 9c of a block 9! adjustably secur d by a screw 32 and slot 93 to the head of the machine. The other limb 94 of the bell-crank lever underlies and cooperates with a downwardly inclined nose or camarm 95 formed on the bracket 57!.

.. In the operation of my improved mechanism The lower electrode 8| is L-shaped in a for limiting and automatically controlling the depth of penetration of the material by the electrodes, the electrode as is set by adjustment of the nut 55 "so that the desired amount of work penetration is obtained when the material under the electrode is at the minimum the machine will be called upon to handle. This adjustment is accomplished by turning the shaft is until the eccentric i'! is at its lowest position and the electrode bar is urged downwardly by the spring 49. With the parts in this position, the nut 55 is adjusted relative to the end of the bar, and the block 9! is adjusted by the screw and slots 92, 93 until the predetermined minimum distance between the electrodes and the maximum time the electrode will remain at its lowest position is obtained. The adjustable parts having been set in their corr ct position, upon operation of the machine the material is advanced between the electrodes and any change in thickness of the material in the bonding zone will cause the roller presser $3 to move up and down in accordanoe with the thickness of the material. This up and down motion is imparted through the vertically movable presser-bar ii and upstanding rod 86 to the pivotally mounted stop member or bell-crank lever 88. The shifting of the bellcrank lever 88 about its pivot 8t varies the position of the upstanding end at of the lever relative to the compl mental cam-arm or nose at and the position of the end 9 of the lever functions as a stop which determines the lowest position to which the electrode-bar as and the electrode 3b can descend. From the above, it will be observed that the lowest position to which the electrode 88 will descend is determined by the thickness of the material between the feed wheels 20 and it and that with any variation in thickness of the material the lowest position to which the electrode 88 descends for any given reciprocation is automatically controlled by the presser mechanism which acts as a work thickness detecting mechanism, thereby positively limiting the depth of work penetration by the electrodes.

Having thus set forth the nature of the invention, what I claim herein is:

1. In an electronic seaming machine having a frame including a work-support, means including an electrode movable toward and from said worksupport for establishing a very high frequency electric field, a work-thickness detecting member dispcsedfor engagement with work in the region of said field, a stop-member fulcrurned upon said frame and controlled by said detecting memher in accordance with variations in the thickness of the work, and a member carried for movement with said electrode and cooperating with said stop member to limit movement of said electrode towards said work-support.

2. In an electronic seaming machine having a frame including a work-support, means including an electrode movable toward and from said work-support for establishing a very high frequency electric field, a work-thickness detecting member disposed for engagement with work in the region of said field, a stop-member fulcrumed upon said frame and variably positioned by said detecting member in accordance with variations in the thickness of the work, a complemental member carried for movement with said electrode and cooperating with said stop-member to limit movement of said electrode toward said work-support, and adjustable means for repositioning said complemented member relatively to said electrode.

3. In an electronic seaming machine having a frame, a reciprocatory electrode bar journaled in said frame, a shaft journaled in said frame and carrying an actuating eccentric, a bracket carried at the upper end of said electrode bar and having two laterally extending portions one of which cooperates with said actuating eccentric and the other cooperating with the frame of the machine to provide a guide, and an adjustable nut threaded on the upper end of said electrode bar for varying the position of the bracket relative to the electrode bar.

4. In an electronic seaming machine having a frame, a reciprocatory electrode bar journaled in said frame, a shaft journaled in said frame and carrying an actuating eccentric, a bracket carried at the upper end of said electrode bar and having a laterally extending portion which cooperates with said actuating eccentric, an adjusting nut threaded for longitudinal movement on the upper end of the electrode bar having a reduced portion embraced by said bracket for adjusting the position of said bracket relative to the bar and a bolt threaded into said bar and having a head portion in looking engagement with said adjusting nut.

5. In an electronic seaming machine, a frame, opposed electrodes carried by said frame, means for establishing a very high frequency electric field between said electrodes, spring means for biasing one of said electrodes towards the other electrode for engagement with work disposed within said field, a work engaging member adapted to yieldingly engage the work and mounted for movement in response to variations in thickness of the work, a bell-crank lever movably mounted on the frame of the machine, said lever being mechanically connected to said work engaging member for movement thereby, and a lug mechanically connected to said spring biased electrode and overlying and cooperating with said lever whereby the depth of work penetration by the electrodes is automatically limited by the position to which said lever is moved by the work engaging member.

6. In an electronic seaming machine, a frame, a lower electrode carried by said frame, an electrode carrying bar journaled in said frame, an upper electrode carried by said bar and cooperating with said lower electrode, a spring for yieldingly urging said upper electrode towards said lower electrode, means for establishing a very high frequency electric field between said electrodes, yielding work engaging mechanism mounted adjacent said electrodes for movement in response to variations in thickness of the work, a stop member located adjacent said electrode bar and secured to the frame of the machine for movement relative to said frame, means for mechanically connecting said stop member with said work engaging member whereby said stop member is moved in accordance with the movement of said work engaging member, and a bracket secured to said electrode bar and having a portion adapted to cooperate with said stop member whereby the depth of work penetration by the electrodes is automatically limited in accordance with the thickness of the work being acted upon by the electrodes.

7. In an electronic seaming machine, a frame, a lower electrode carried by said frame, an electrode carrying bar journaled in said frame, an

upper electrode carried by said bar and cooperating with said lower electrode, a spring for yieldingly urging said upper electrode towards said lower electrode, means for establishing a very high frequency electric field between said electrodes, yielding work engaging mechanism mounted adjacent said electrodes for movement in response to variations in thickness of the work, a stop lever located adjacent said electrode bar and pivotally secured to the frame of the machine, mechanism operatively connecting said work engaging member with said lever whereby said lever is moved in accordance with the movement of said work engaging member, and means secured to said electrode bar and cooperating with said stop lever for automatically limiting the degree of approach of said electrodes toward each other in accordance with the thickness of the work being operated upon.

8. In an electronic seaming machine, a frame, opposed electrodes carried by said frame, means for establishing a very high frequency electric field between said electrodes, mechanism for moving one of said electrodes toward and from the other electrode for engagement with work disposed between said electrodes, and automatic mechanism for controlling the depth of work penetration of said movable electrode in accordance with variations in the thickness of the work between the electrodes comprising, a workthickness detecting mechanism disposed for engagement with the work at a point adjacent said electrodes, a stop member connected to said electrode, a second stop member carried by the frame of said machine and cooperating with said first stop member to limit its downward movement, said second stop member being shiftable to various effective positions, and a mechanical connection between said second stop member and said work-thickness detecting mechanism whereby the position of said stop member is varied in accordance with the thickness of the work between said electrodes.

9. In an electronic seaming machine, opposed electrodes, means for establishing a very high frequency electric field between said electrodes, mechanism for moving one of said electrodes toward the other electrode for engagement with work disposed between said electrodes, stop means associated with said electrodes and movable to various positions for limiting the approach of the movable electrode toward the stationary electrode, a work-thickness detectin mechanism disposed for engagement with the work at a point adjacent said electrodes, means yieldingly biasing said detecting member into engagement with the work being acted on by said electrodes, and mechanism actuated by said work-thickness detecting member and operatively connected to said stop means for varying the position of said stop means in accordance with variations in the thickness of the work.

ELLSWORTH B. SNYDER.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 2,432,412 Hacklander Dec. 9, 1947 2,458,059 Christensen et al. Jan. 4, 1949 2,473,143 Graham et a1. June 14, 1949 2,509,595 Hacklander May 30, 1950 

